Added Damm algorithm

1 files changed, 32 insertions, 0 deletions

diff --git a/damm/damm_test.go b/damm/damm_test.go
new file mode 100644
index 0000000..1f338b8
--- /dev/null
+++ b/damm/damm_test.go
@@ -0,0 +1,32 @@
+package damm
+
+import (
+	"log"
+	"testing"
+
+	"github.com/neonxp/checksum"
+)
+
+func TestLuhn(t *testing.T) {
+	samples := map[string]error{
+		"456126121234546": checksum.ErrInvalidChecksum,
+		"A56126121234546": checksum.ErrInvalidNumber,
+		"5724":            nil,
+	}
+	for num, result := range samples {
+		if err := Check(num); err != result {
+			t.Errorf("Expected %+v actual %+v for %s", result, err, num)
+		}
+	}
+
+	num := "572"
+	checksum, err := Generate(num)
+	if err != nil {
+		t.Error(err)
+	}
+	numberWithChecksum := num + checksum
+	log.Println(numberWithChecksum)
+	if err := Check(numberWithChecksum); err != nil {
+		t.Errorf("Expected no error actual %+v for %s", err, numberWithChecksum)
+	}
+}